A. Field Of The Invention.
The present invention relates to gauges used to measure the level of fuel in a fuel tank where the tank contains a gas/oil mixture. The gauge of the present invention provides information relating to how to refill such a tank with a specified gas/oil mixture of fuel.
B. Description Of The Art.
Various engines use a mixture of gas and oil as their fuel. For example, engines in lawn mowers, snow blowers, outboards, motorcycles, tractors, chain saws and golf carts often use a 50:1 gas/oil fuel. With such ratios, relatively small errors in mixing gas and oil can affect engine performance and wear. Further, even where the gas and oil are correctly mixed it is difficult to correctly estimate the amount of fuel required to fill the tank.
In practice, greater than the needed amount of fuel is often mixed and the excess must then be separately stored (thereby creating a safety hazard and/or taking up space) or wasted. Moreover, the typical means of mixing the fuel involves using a separate mixing container. This leads to waste (as well as to pollution problems if the mixing container is cleaned out).
Purchasing a commercially mixed gas/oil fuel is a possibility, but this leads to storage problems and to a lack of flexibility where different engines use different ratio fuel. More importantly, consumers often prefer to be able to mix the fuel from readily available supplies of gas (which many consumers store anyway for use with their automobile).
The art has developed a fuel tank dip stick which has along its side a conversion scale to provide information as to the amount of oil to be added prior to refilling the tank with gas. While this system is an improvement, it has its own problems. For example, the user should preferably wipe off the dip stick to obtain the most accurate reading, with the resulting undesirable residue on the wiping cloth. Further, differences in fuel viscosity, the manner that the dip stick is pulled out and inserted, and splashing can lead to inaccuracies. Also, the system is awkward and requires the user to leave the tank open longer than necessary while reading the dip stick. This is of concern from an air pollution standpoint.
It can therefore be seen that a need has existed for an improved means for filling a tank with a selected gas/oil ratio fuel mixture.